My daughter asked me if I had some idea how to store the many sewing thread spools and corresponding machine bobbins which started to accumulate since she got her new sewing machine. Fortunately I never threw away my empty CD/DVD spindles, always thinking that "some day" I will find something useful to do with them... So this little project builds a carousel for storing sewing thread spools inside an empty 50-CD/DVD spindle. :) The carousel consists of a round base plate for two concentric rings of spools and the corresponding number of spears onto which the thread spools are stuck. The spears are mounted on the base plate by sliding them into the corresponding rails. The top of the spears is hollow and acts as a compressible clamp for retaining a machine bobbin for the lower thread of the same color as the main spool on this spear. Given that the clamp need to have some flexibility, ABS is the material of choice for this project. The SCAD source is fully parametrized, so it can easily be adapted to special needs. In addition to the basic construction modules, specific modules are provided for some useful configurations, this include four carousels for For these configurations, ready-to-print STL files for the base plate are provided. As the same spears are used for all carousels, you just need to print the required total number of spears (plus maybe 2 or 3 spares) by combining the provides STL files for 1, 2, 5 and 10 spears. Note that the normal spears assume that the inner diameter of the sewing thread spool is at least 6.5mm. The heads of the normal spears can accommodate a machine bobbin with an inner diameter of 6mm (1/4"). For spools with inner diameters smaller than 6.5mm, you can used the narrow version of the spears. Note that the normal and the narrow spears have the same sliding rail, so they can be mixed on the same base plate.For this project you'll need an empty 50-disc CD or DVD spindle including it's transparent plastic cover. Print the desired carousel base plate plus the required number of spears. Attach the spears to the base plate by pushing them into the rails on the base plate. They should fit firmly, so a little force is needed to push them into place. I printed the plastic parts from 3mm ABS filament on my DIY Prusa i3, using a 0.4mm nozzle with 0.56mm extrusion width and 0.25 layer height. I print on a clear mirror without Kapton tape, but thoroughly cleaned with acetone first and then with double concentrated lemon juice.